Pediatr Gastroenterol Hepatol Nutr.  2014 Mar;17(1):37-40.

Molecular Analysis of the UGT1A1 Gene in Korean Patients with Crigler-Najjar Syndrome Type II

• Ko JS
• Chang JY
• Moon JS
• Yang HR
• Seo JK

Abstract

PURPOSE
Crigler-Najjar syndrome type II (CN-2) is characterized by moderate non-hemolytic unconjugated hyperbilirubinemia as a result of severe deficiency of bilirubin uridine diphosphate-glucuronosyltransferase (UGT1A1). The study investigated the mutation spectrum of UGT1A1 gene in Korean children with CN-2.
METHODS
Five Korean CN-2 patients from five unrelated families and 50 healthy controls were enrolled. All five exons and flanking introns of the UGT1A1 gene were amplified by polymerase chain reaction (PCR) and the PCR products were directly sequenced.
RESULTS
All children initially presented with neonatal jaundice and had persistent indirect hyperbilirubinemia. Homozygous p.Y486D was identified in all five patients. Three patients had an associated homozygous p.G71R and two a heterozygous p.G71R. The allele frequency of p.Y486D and p.G71R in healthy controls was 0 and 0.16, respectively. No significant difference in mean serum bilirubin levels was found between homozygous carriers of p.G71R and heterozygous carriers.
CONCLUSION
The combination of homozygous p.Y486D and homozygous or heterozygous p.G71R is identified. The p.Y486D and p.G71R can be screened for the mutation analysis of UGT1A1 in Korean CN-2 patients.

Keyword

Crigler-Najjar syndrome; Bilirubin uridine-diphosphoglucuronosyl transferase 1A1; Mutation; Bilirubin

MeSH Terms

Bilirubin
Child
Crigler-Najjar Syndrome*
Exons
Gene Frequency
Humans
Hyperbilirubinemia
Infant, Newborn
Introns
Jaundice, Neonatal
Polymerase Chain Reaction
Uridine
Bilirubin
Uridine

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